Primary cerebellar agenesis presenting as isolated cognitive impairment.

Primary cerebellar agenesis is a rare entity. To the best of our knowledge, eleven living cases have been reported till date. Most of these were associated with some degree of motor impairment. We present a case of cerebellar agenesis in a child who presented with cognitive abnormalities leading to poor performance at school. No motor impairment was seen. Among the eleven cases reported earlier, only one case showed lack of motor impairment.